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During the production of lithium ion battery’s raw material, large numbers of lithium slag would come into being whose main chemical components are LiO2,SiO2,Al2O3 etc.
Levigate it to 9150cm2/g, average grain size 3.03µm and proportion 2.45g/cm3 using MZL100 binocular vibration mill; Water Reducing Agent: Sulphamic acid is superplasticizer whose water-reducing rate is higher than 25%; Fine Aggregate: Jianyang City of Sichuan Province produces medium sand whose apparent density is 2.70g/cm3, bulk density is 1.76g/cm3, moisture content is 0.61% and fineness modulus is 2.36; Coarse Aggregate: Limestone macadam, Dmax=20mm，5mm~20mm continuous grading, crush index 10.3% and apparent density2.90g/cm3.
As dosage of water reducing agent is high, slumps of concrete mixture increases a lot whose number is close to pumping requirement.
Therefore mountain powder grains fill in cement grains, voids between cement grains and interfaces and lattices of cement hydration products whose function is similar to “Ball”.

Fig. 2 shows the resistivity of composite particles decreases with the increase of the grain size of copper powder.
This is because that copper powder with coarse grains, the silver content after coating is relatively high, it is positive for conductivity.
While the temperature is increasing, the activity of silver ion increases and its contact with copper powder grains become easier [5].
In 6b) silver sediment is also granular and silver grains clearly increase in number.
The silver grains are, however, single grains rather than continuous and the copper powder base is clearly visible. 6c) shows that the silver sediment has formed islands or joined together and a layer has emerged at the edge of flake copper powder.

The development of strain concentrations at strain-induced ferrite films (5-20 µm thick) formed at austenite grain boundaries [1,2] is among the grain boundary cracking mechanisms that have been suggested to explain the loss of ductility at temperatures near Ar3.
Attempts have been made to explain this unusually high temperature in terms of weakening of austenite grain boundaries by formation of precipitate free-zones (PFZ) [3].
Knowledge of Ar3 transformation temperature is of great importance for the design of hot rolling schedules and a number of experimental methods have been proposed [6].
It appears that the irregular grains nucleated at austenite grain boundaries and grew during the isothermal holding in a manner similar to pro-eutectoid ferrite in low C-Mn steels.
Isothermal transformation of austenite to ferrite in this steel occurs very fast at temperatures as high as 950 °C by nucleation at austenite grain boundaries.

The FSP is widely used for fabrication of surface composites and also used for grain structure refining and strengthening.
The Abdollahi et al developed a surface composites of Mg- Al- Zn (AZ31) by FSP and demonstrate the influence of no. passes on grain refinement and reported a grain size reduction from 25µ to 3 µ from 1 pass to 5th pass of FSP also reported a significant improvement in hardness[5].
Al reported a grain size reduction from 84µm to 3µm in a single pass [16].
The spray forming produce high density, fine grain microstructure.
A number of research studies on the development of magnesium MMC using the spray forming method have examined the relationships between the spray processing parameters, the microstructure, and the mechanical properties of the composites[52][53][54].

Ferrite stainless steel has many unique features and advantages, such as low cost, price stability, it can take the place of austenitic stainless steel in a number of areas.
Whereas the microstructure of hot rolled sheet after normalizing is polygon and equiaxial grain, look at figure 1(b).
This is mainly because that annealed sheet stands recrystallization; it makes the elonggated grain into the equiaxial shape.
It accomplishes recrystallization after normalizing and its elonggated grain transforms into polygonal and equizxed grain.
The microstructure of final annealed sheet is made up by uniform, tiny recrystallizational grain

In Fig. 3 (a) and (b), the light grains with smaller size marked as A are Ba0.55Sr0.40Ca0.05TiO3 and the dark grains with larger size marked as B are Mg2TiO4.
When the BST particles are coated with MgO, Fig. 3 (c) and (d) shows that grains marked as C and D represent Ba0.55Sr0.40Ca0.05TiO3 and Mg2TiO4 respectively.
The intrinsic loss is caused by the lattice vibration modes, while the extrinsic loss is dominated by vacancies, second phases, grain sizes, and densification/porosity.
The coating of MgO improves the wetting property between BST and MT grains during the sintering process.
The reduction of extrinsic loss number is important reason for the decrease of dielectric loss.

Moreover, magnetic field has some effects on crystal orientation during the crystallization process of the grain, whose driving force is related to the magnetocrystalline anisotropy energy [17, 18].
These results can be explained by the refinement of grains and the increase of cell volume.
Fig. 4 The relationship of discharge capacities with cycle numbers: (a) MlNi3.6Co0.7Mn0.4Al0.3; (b) MlNi3.6Co0.35Mn0.5Al0.3Cu0.25.
The refinement of grains is also an advantage for better kinetic properties.
There is a significant oriented growth for MlNi3.6Co0.35Mn0.5Al0.3Cu0.25 alloys and the grains are refined

In the fusion weld after T6 heat treatment the average plane section area of the α-Mg grain amounts to 1440μm2 and is almost three times less than the grains of the base material (Fig. 2c, Table 3).
This is caused by high heterogeneity of the chemical composition of the fusion weld area resulting from the segregation of the alloy elements in the liquid metal pool and from the development of a greater number of nuclei of crystallization.
The structure of the base material consists of the α-Mg solid solution grains (Fig. 4a), with an average plane section area of the grain of 5333μm2 (Table 3) and fine precipitates of the intermetallic phases containing yttrium and neodymium (Fig. 4b, d ) found in the entire volume of the grains.
The average plane section area of the α-Mg base material grain amounts to 4208µm2, whereas in the fusion weld the α-Mg grain is three times smaller (Ā = 1440 μm2).
· After annealing at the temperature of 250oC for 1000 hours the size of the grain of the base material amounted to 5333µm2 and the grain size in the fusion weld was 1118μm2.

The XRD results showed that the doping of lanthanum could not only efficiently inhibit the grain growth but also suppress the phase transition of anatase to rutile.
The surface area, adsorption capacity for organic compounds and the number of surface oxygen vacancies and defects were increased by lanthanum doping.
The decrease in crystallite size can be attributed to segregation of the formation of La2O3 at the grain boundary or the presence of Ti-O-La bond, which inhibited the growth of crystal grains by restricting the coalescence of some smaller neighboring grains.

The X- ray density of the prepared samples was calculated using the relation [9]: Dx = 8MNa3 (1) where M is the molecular weight and N is the Avogadro's number.
The formation of pores within the grain or grain boundaries may be responsible for the observed decrease in density.
With high rate of grain growth, pores may be left behind by moving the grain boundaries as a result pores are trapped inside grains.
This model, suggests that dielectric medium is made of well conducting grains, separated by poorly conducting grain boundaries.
At lower frequencies the grain boundaries are more effective than grains in electrical conduction.